WO2011089265A1

WO2011089265A1 - Use of fatty acid compounds for lowering blood glucose levels

Info

Publication number: WO2011089265A1
Application number: PCT/EP2011/050967
Authority: WO
Inventors: Jenny Frederiksson; Mads Tang Christensen
Original assignee: Bridge Bioresearch Plc; Jenny Frederiksson
Priority date: 2010-01-25
Filing date: 2011-01-25
Publication date: 2011-07-28

Abstract

Use of a compound of the general formula (I), COOH-CHR-(CH₂)m-CH=CH-(CH₂)n-CH₃ (I), wherein R can be any group with a molecular weight from 14 to 200 Da, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration or a mixture thereof, or a pharmaceutically acceptable salt, ester or glyceride thereof, for preparing a pharmaceutical composition for lowering blood glucose.

Description

Use of fatty acid compounds for lowering blood glucose levels Field of invention

The present invention relates to the use of 2-hydroxyoleic acid and related fatty acid compounds, or pharmaceutically acceptable salts, esters or glycerides thereof, for lowering blood glucose levels.

Background of invention

Fatty acids are aliphatic mono-carboxylic acids derived from, or contained in esterified form in, an animal or vegetable fat, oil, or wax. Natural fatty acids commonly have a chain of 4 to 28 carbons, which may be saturated or unsaturated. Saturated fatty acids are long-chain carboxylic acids that usually have between 12 and 24 carbon atoms and no double bonds. Unsaturated fatty acids are of similar form, except that one (monounsaturated fatty acid, MUFA) or more (polyunsaturated fatty acid, PUFA) alkenyl functional groups exist along the chain, with each alkene substituting a single- bonded " -CH₂-CH₂-" part of the chain with a double-bonded "-CH=CH-" portion (that is, a carbon double-bonded to another carbon). Polyunsaturated fat can be found mostly in grain products, fish and sea-food (herring, salmon, mackerel, and halibut), soybeans, and fish oil. Monounsaturated fats are found in natural foods such as nuts and avocados, and are the main component of olive oil. Common monounsaturated fatty acids are palmitoleic acid, cis-vaccenic acid and oleic acid.

Fatty acids are commercially used for soaps, synthetic organic detergents, lubricating greases, surface coatings, emulsifiers, cosmetics and in the food industry.

Recently, synthetic derivatives of fatty acids have also been shown to exhibit beneficial health properties such as for example to act as agents for inducing reductions in body weight. Obesity is a pathophysiological condition in which body fat has accumulated to an extent that it exerts an adverse effect on health. Obesity typically promotes the appearance of a cluster of other interrelated diseases, in particular cardiovascular diseases, e.g., hypertension, atherogenic dyslipidemia, insulin resistance and type 2 diabetes. Insulin resistance is the condition in which normal amounts of insulin are inadequate to produce a normal insulin response from fat, muscle and liver cells resulting in elevated blood glucose levels. Type 2 diabetes, is characterized by persistent hyperglycemia from any of several causes and is the most prominent disease related to failure of blood sugar regulation. High blood glucose levels subsequently promote a number of secondary, irreversible health dysfunctions, for example vascular macro- and microangiopathy, and for that reason, it is of high importance to avoid incidences of hyperglycemia.

EP1435235 describes the use of hydroxyoleic (2-hydroxyoleic) acid and molecules of a similar structure as antitumor agents, as agents with hypotensive activity and as agents for inducing reductions in body weight. EP1435235 does not disclose the use of hydroxyoleic (2-hydroxyoleic) acid and molecules of a similar structure for lowering blood glucose levels in a subject in need thereof.

WO 2005/041691 discloses the use of hydroxyoleic (2-hydroxyoleic) acid and related compounds as functional food additives, which can be used in the manufacture of ingredients, dietary products, acceptable food forms and food in general, focusing on improving parameters related to cardiovascular diseases, such as hypertension and obesity. The document does not disclose the use of hydroxyoleic (2-hydroxyoleic) acid and molecules of a similar structure for lowering blood glucose levels in a subject in need thereof.

WO 2007/069758 is directed to compositions for activating PPARa and PPARy. The composition comprises a hydroxy fatty acid and/or an epoxy fatty acid having a PPARa ligand activity and/or a PPARy ligand activity and/or a mono-, di- or tri-glyceride comprising the hydroxy fatty acid and/or epoxy fatty acid as a fatty acid-constituting component. The composition can be used for the treatment, prevention or amelioration of insulin resistance, diabetes, obesity, hyperlipemia, arteriosclerosis or a coronary artery disease. The invention disclosed in WO 2007/069758 embraces both saturated fatty acids and unsaturated fatty acids. Among the unsaturated fatty acids hydroxy oleic acid, dihydroxy oleic acid and epoxy oleic acid is mentioned in general, and 12,13- epoxy oleic acid, 9,10-epoxy-12-octadecenoic acid, 12-hydroxy-9-octadecenoic acid and 12,13-dihydroxy oleic acid are mentioned specifically. The document does not disclose any unsaturated fatty acids, which are substituted in the 2-position. Neither does the document disclose the use of any of the above mentioned hydroxy fatty acid and/or an epoxy fatty acid for lowering blood glucose levels in a subject in need thereof.

Yokoi et al. have isolated and investigated 6 different unsaturated hydroxy fatty acids for the PPAR activity. These fatty acids were 13-hydroxy-(9E,1 1 E)-octadecadienoic acid, 9-hydroxy-(10E,12E)-octadecadienoic acid, 9-hydroxy-(10E)- octadecadienoic acid, 10-hydroxy-(8E)-octadecadienoic acid, 8-hydroxy-(9E)-octadecenoic acid, and 1 1 -hydroxy-(9Z)-octadecenoic acid (see Yukoi Hiroshi et al., Biol. Pharm. Bull. 32(4), 735-740, 2009). 9-hydroxy-(10E,12E)-octadecadienoic acid exhibited the most potent PPARy agonist activity. The document does not disclose any unsaturated fatty acids, which are substituted in the 2-position. Neither does the document disclose the use of any of the above mentioned hydroxy fatty acid and/or an epoxy fatty acid for lowering blood glucose levels in a subject in need thereof. WO 92/01450 is directed to food and pharmaceutical compositions, which contain amounts of short chain monosaturated fatty acids or their derivatives sufficient to increase the content of fatty acids within the tissues when said compositions are administered and to substantially improve the metabolic processing of lipids within animals.

WO 2009/017802 describes the use of nitro oleic acid and related metabolites for use as agonists of PPAR-γ. It was found that nitro oleic acid was a more potent agonist of PPAR-γ relative to nitro linoleic acid. It is further disclosed that nitro oleic acid and its metabolites as well as their pharmaceutically acceptable salts and prodrug forms, are candidate therapeutics for the treatment of type-2-diabetes, which results from insulin resistance accompanying the improper functioning of PPAR-γ. This document, however, is particular concerned with the use of 9- or 10-nitro octadecenoic acids.

JP 2008 156296 discloses the use of trihydroxyoctadecadienoic acid as a functional fatty acid to provide a metabolic syndrome ameliorator to prevent and ameliorate metabolic syndrome and to provide drinks and foods each containing trihydroxyoctadecadienoic acid. Summary of invention

The problem to be solved by the present invention is to provide a new medical use for 2-hydroxyoleic acid and related fatty acid as well as derivatives thereof. Based on detailed work (see working examples herein) the present inventors found that by administrating 2-hydroxyoleic acid to animals that had been fed an energy-dense high-fat diet for 14 weeks such that they had become obese and exhibited elevated blood glucose levels when compared to animals that had been feed a normal diet, it was possible to lower the blood glucose level to the same level as in animals that had received a normal diet (example 1 and 2 herein). In other words, treatment of obese animals with 2-hydroxyoleic acid provided normal blood glucose levels.

For instance, example 1 of the present invention shows that animals, which had been feed an energy-dense high-fat diet, had become obese and exhibited approximately a 28% increased blood glucose level as compared to the animals that had received the normal low fat diet. After treatment of the animals that had received such an energy- dense high-fat diet with 2-hydroxyoleic acid for 30 days, these animals displayed similar blood glucose levels as animals that had been kept on a normal low fat diet. In contrast, no effect on the blood glucose levels was observed when the anti-obesity agent sibutramine was administered to such obese animals with elevated blood glucose levels. Thus, the ability of 2-hydroxyoleic acid to normalize the blood glucose level in obese subjects is not a general effect of all anti-obese compounds and suggests that 2-hydroxyoleic acid acts through a different mechanism than sibutramine. It is well established that the use of mice fed a high fat diet is a good robust animal model for corresponding effects in humans.

Furthermore, it has surprisingly been shown that 2-hydroxyoleic acid, sodium salt restores normoglycaemia in a non-obese mouse model of impaired glucose tolerance, which demonstrates that the anti-diabetic effect of 2-hydroxyoleate is independent of any anti-obesity action (example 3). Moreover, it has surprisingly been found that although sibutramine (a well known anti-obesity agent) and 2-hydroxy oleate induced a similar level of fat loss, only 2-hydroxyoleate significantly lowered the fasting blood glucose level (example 4). It is also well established that obese human subjects in general possess elevated blood glucose levels and have a high prevalence for developing diabetes. Thus, by lowering or normalizing the blood glucose level in a human subject suffering from diabetes, the subject will need lower amounts of insulin to maintain a tight regulation of the blood glucose level, which is of high importance for reducing or avoiding the likelihood of complications that usually is accompanied with obesity and diabetes such as respiratory problems, certain types of cancer, osteoarthritis, and cardiovascular diseases. An advantage of using 2-hydroxyoleic acid, or a derivative thereof, such as a related fatty acid derivative, for lowering the blood glucose level is that such compounds not only lowers the blood glucose level but also improves the blood pressure and decrease the body weight of a subject in need thereof. On the contrary, if sibutramine is administered to an obese subject no such beneficial effect on the normalization of the blood glucose level is observed. Moreover a side effect of sibutramine is a tendency to raise blood pressure. Thus, 2-hydroxyoleic acid, or a derivative thereof, possess the ability to treat or prevent several of the most important implications in obese or diabetic subjects. Especially, according to the present invention 2-hydroxyoleic acid, or a derivative thereof, may be used to treat high levels of blood glucose. In particular, 2- hydroxyoleic acid, or a derivative thereof, may be used in the treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia.

A further advantage with respect to 2-hydroxyoleic acid, or a derivative thereof, is that in contrast to compounds with similar effects, such as for instance exendin-4 (an incretin mimetic agent) or liraglutide (a glucagon-like peptide (GLP-1 ) analogue) that are intended for subcutaneous injections, 2-hydroxyoleic acid and analogues thereof are intended for oral administration thereby increasing patient compliance. Definitions

Prior to a discussion of the detailed embodiments of the invention is provided a definition of specific terms related to the main aspects and embodiments of the invention. The term "general formula (I)" means a compound with a structure such as COOH- CHR-(CH₂)m-CH=CH-(CH₂)n-CH₃ in which R can be any group with a molecular weight from 14 to 200 Da, but preferably R is selected from OH, amino, d-₆alkyl, C^alkenyl, C₂-₆alkynyl, d-₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration, preferably in the cis configuration, or a pharmaceutically acceptable salt, ester or glyceride thereof.

The term "diabetes type 2" also called non-insulin-dependent diabetes mellitus (NIDDM) or diabetes mellitus type 2 means herein a chronic (lifelong) disease marked by high levels of sugar (glucose) in the blood. Type 2 diabetes is the most common form of diabetes. It usually occurs in adulthood, but young people are increasingly being diagnosed with this disease. Diabetes type 2 is characterized by high blood glucose in the context of insulin resistance (i.e. that the cells do not respond appropriately when insulin is present) and relative insulin deficiency. Type 2 diabetes is becoming more common due to increasing obesity and failure to exercise.

The term "insulin resistance syndrome" or "insulin resistance" is a condition in which normal amounts of insulin are inadequate to produce a normal insulin response from fat, muscle and liver cells.

The term "Syndrome X" also called metabolic syndrome X or just metabolic syndrome is a grouping of cardiac risk factors including insulin resistance, obesity (especially abdominal obesity), high blood pressure, abnormalities in blood clotting, and lipid abnormalities. According to the International Diabetes Federation Syndrome X is defined as:

Central obesity (defined as waist circumference (If BMI is >30 kg/m², central obesity can be assumed and waist circumference does not need to be measured) with ethnicity specific values) and any two of the following:

- Raised triglycerides: >150 mg/dL (1 .7 mmol/L), or specific treatment for this lipid abnormality.

- Reduced HDL cholesterol: <40 mg/dL (1 .03 mmol/L) in males, <50 mg/dL (1 .29 mmol/L) in females, or specific treatment for this lipid abnormality.

- Raised blood pressure: systolic BP >130 or diastolic BP >85 mm Hg, or treatment of previously diagnosed hypertension. - Raised fasting plasma glucose: FPG >100 mg/dL (5.6 mmol/L), or previously diagnosed type 2 diabetes. If FPG >5.6 mmol/L or 100 mg/dL, OGTT Glucose tolerance test is strongly recommended but is not necessary to define presence of the Syndrome.

The term "Impaired glucose tolerance" means herein a pre-diabetic state of dysglycemia. According to the criteria of the American Diabetes Association, impaired glucose tolerance is defined as:

Two-hour glucose levels of 140 to 199 mg per dL (7.8 to 1 1 .0 mmol) on the 75-g oral glucose tolerance test. A patient is said to be under the condition of IGT when he/she has an intermediately raised glucose level after 2 hours, but less than would qualify for type 2 diabetes mellitus. The fasting glucose may be either normal or mildly elevated.

The term "hyperglycemia" means herein a condition in which an excessive amount of glucose circulates in the blood plasma. This is generally a blood glucose level of more than 10 mmol/L (180 mg/dl), but symptoms may not start to become noticeable until levels as high as 15-20 mmol/L (270-360 mg/dl).

The term "2-hydroxyoleic acid" means octadecenoic acid C18:1 cisA9 or cis-2-hydroxy- 9-octadecenoic acid and is schematically represented below.

The term "derivative" or "derivatives" means those fatty acids that have the double bond shifted one or two positions from the central zone and/or that have the double bond shifted from one to five positions from the central zone and/or have from one to four carbon atoms (CH₂ groups) more or less on each side of the double bond and/or that have a residue (R) in position 2 different from OH, with a small atomic mass (Mw less than or equal to 200 Da), and the stereoisomer corresponding to the projection of the R group in general formula (I) is in R- or S-configuration or racemic mixtures thereof.

The term a "therapeutically effective amount" of 2-hydroxyoleic acid or a compound of general formula (I), as used herein, means an amount sufficient to cure, alleviate or partially arrest the clinical manifestations of a given disease and its complications. Accordingly, an amount adequate to accomplish a lowering of the blood glucose level is defined as a "therapeutically effective amount". Effective amounts for each purpose will depend on the severity of the disease, i.e. the diabetes type 2, the insulin resistance syndrome etc, as well as the weight and general state of the subject.

The term "treatment" and "treating" as used herein means the management and care of a patient for the purpose of combating a condition, such as a disease or a disorder. The term is intended to include the full spectrum of treatments for a given disorder or condition from which the patient is suffering by administration of the 2-hydroxyoleic acid or a compound of general formula (I), or a pharmaceutically acceptable salt, ester or glyceride thereof, thereof. More particularly, the term refers to alleviate or relief the symptoms and complications associated with the disorder or disease, to delay the progress of the disorder or disease or to cure or eliminate the disorder or disease by administering to a subject the 2-hydroxyoleic acid or a compound of general formula (I), or a pharmaceutically acceptable salt, ester or glyceride thereof, whereby the blood glucose level is lowered or normalized. The patient to be treated may preferably be a mammal including, but not limited to, animals, such as human beings, dogs, cats, cows, sheep and pigs, but preferably the patient to be treated is a human being, or a dog or a cat.

The term "a pharmaceutically acceptable salt" is intended to indicate salts, which are not harmful to the patient. Such salts are generally prepared by reacting the free base with a suitable organic or inorganic acid or by reacting the free acid with a suitable organic or inorganic base. When a compound according to the present invention comprises a free base (e.g. -NH₂) such salts are prepared in a conventional manner by treating a solution or suspension of the compound with a chemical equivalent of a pharmaceutically acceptable acid. When a compound according to the present invention comprises a free acid (e.g. -COOH) such salts are prepared in a conventional manner by treating a solution or suspension of the compound with a chemical equivalent of a pharmaceutically acceptable base. Physiologically acceptable salts of a compound with an acid group include the anion of said compound in combination with a suitable cation such as sodium or ammonium ion. Other examples of pharmaceutically acceptable salts include metal salts, ammonium and alkylated ammonium salts, salts of inorganic acids as well as organic acids. Representative examples of suitable inorganic acids include hydrochloric, hydrobromic, hydroiodic, phosphoric, sulfuric, nitric acids and the like. Representative examples of suitable organic acids include formic, acetic, trichloroacetic, trifluoroacetic, propionic, benzoic, cinnamic, citric, fumaric, glycolic, lactic, maleic, malic, malonic, mandelic, oxalic, picric, pyruvic, salicylic, succinic, methanesulfonic, ethanesulfonic, tartaric, ascorbic, pamoic, bismethylene salicylic, ethanedisulfonic, gluconic, citraconic, aspartic, stearic, palmitic, EDTA, glycolic, p-aminobenzoic, glutamic, benzenesulfonic, p-toluenesulfonic acids and the like. Further examples of pharmaceutically acceptable inorganic or organic acid addition salts include the pharmaceutically acceptable salts listed in Berge, et al., J. Pharm. Sci. 1977, 66, 2. Examples of metal salts include lithium, sodium, potassium, magnesium salts and the like. Examples of ammonium and alkylated ammonium salts include ammonium, methylammonium, dimethylammonium, trimethylammonium, ethylammonium, hydroxyethylammonium, diethylammonium, butylammonium, tetramethylammonium salts and the like.

The term "a pharmaceutically acceptable ester" is intended to indicate the product where the acid of general formula (I) has reacted with an alcohol and formed the resulting ester compound. Preferred alcohols that can be used for producing such an ester compound include, but are not limited to, methanol, ethanol, n-propanol and isopropanol.

The term "a pharmaceutically acceptable glyceride" is intended to indicate the product where at least one acid of general formula (I) has reacted with glycerol and formed the resulting ester compound. The term includes mono-, di- and triglycerides indicating that one, two or three fatty acids have reacted with the glycerol. It should be understood that the scope of the present invention includes compounds, for which at least one acid of general formula (I) has reacted with the glycerol. Hence, a triglyceride, which for example has been produced by reacting glycerol with one acid of general formula (I) and two acids, which are different from the general formula (I), is also encompassed in the present invention by the term "a pharmaceutically acceptable glyceride". The term "pharmaceutical composition" is to be understood as a wide variety of pharmaceutical acceptable formulations and may be combined with one or more physiologically acceptable carriers. The pharmaceutical carrier or diluent employed may be a conventional solid or liquid carrier or diluent. Examples of solid carriers are lactose, terra alba, sucrose, cyclodextrin, talc, gelatin, agar, pectin, acacia, magnesium stearate, stearic acid or lower alkyl ethers of cellulose. Examples of liquid carriers are syrup, peanut oil, olive oil, phospholipids, sterols, fatty acids, fatty acid amines, polyoxyethylene, isotonic buffer solutions and water.

Embodiments of the present invention are described below, by way of examples only. Description of drawings

Figure 1 : This figure shows the effect of 2-hydroxyoleic acid on the glucose homeostasis in male C57BL/6J mice as measured by an oral glucose tolerance test (Example 1 ). The blood glucose levels were measured in mice, which had been offered a low fat diet (LF control), an energy-dense high fat diet (HF-control), an energy-dense high fat diet and 2-hydroxyoleic acid (2-OHOA), or an energy-dense high fat diet and sibutramine (Sibutramine). Blood samples for blood glucose measurements were taken at time points 0, 15, 30, 60, and 120 after oral administration of 2g/kg glucose (Figure 1 A). Blood glucose levels were determined as measures for glucose clearance as evaluated by calculating the area under the curve (AUC) (Figure 1 B).

Figure 2: This figure shows the effect of 2-hydroxyoleic acid on body weight (Figure 2A and 2B), fastening blood glucose level (figure 2C) and blood glucose level 120 min after initiation of an oral glucose tolerance test (figure 2D) in mice (Example 3). The mice were divided into five groups and were offered either a normal low fat diet (LF control) or a high fat, low carbohydrate diet (HF control, Rosiglitazone, 2-OHOA, 2- OHSA). The different groups were treated with vehicle (LF Control and HF Control), rosiglitazone (Rosiglitazone), 2-hydroxyoleic acid (2-OHOA) or 2-hydroxystearic acid (2-OHSA). Body weight was determined on day 0 and on day 14 of treatment and the shown blood glucose levels were determined after 14 days of treatment.

Figure 3: This figure shows the effect of 2-hydroxyoleate on body weight over a period of 24 days of administration (figure 3A) and the blood glucose level on day 7 (figure 3B) and on day 15 (figure 3C) measured by an oral glucose tolerance test. The mice were divided into four groups that all were offered a high fat diet (SDS Western diet). One group was treated with 2-hydroxyoleic acid sodium salt (2-OHOA). A second group was fed ad-lib (vehicle), and a third group was pair-fed to the group of mice that were given 2-hydroxyoleate (vehicle pair-fed). The last group was given the anti-obesity drug sibutramine (Sibutramine).

Detailed description of the invention

Diabetes mellitus type 2 - also known as non-insulin-dependent diabetes mellitus (NIDDM) or adult-onset diabetes - is a metabolic disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency. Diabetes is often initially managed by increasing exercise and dietary modification. As the condition progresses, medications may be needed. It is recognised that type 2 diabetes is due to a combination of lifestyle and genetic factors. A number of lifestyle factors are known to be important for the development of type 2 diabetes. It has for example been shown that people, who had high levels of physical activity, a healthy diet, did not smoke, and consumed alcohol only in moderate amounts, had an 82% lower rate of diabetes.

Obesity has been found to contribute to approximately 55% of cases of type 2 diabetes, and decreasing consumption of saturated fats and trans fatty acids while replacing them with unsaturated fats may decrease the risk. The increased rate of childhood obesity in recent years is believed to have led to the increase in type 2 diabetes in children and adolescents.

Obesity is a pathophysiological condition in which body fat has accumulated to an extent that it exerts an adverse effect on health leading to physical constraints measurable in disability-adjusted-life-years and reduced life expectancy. Obesity is most commonly caused by a combination of excessive dietary calories, lack of physical activity, and genetic susceptibility.

The World Health Organization (WHO) defines "overweight" as a BMI equal to or more than 25, and "obesity" as a BMI equal to or more than 30. These cut-off points provide a benchmark for individual assessment, but there is evidence that risk of chronic disease in population's increases progressively from a BMI of 21 .

Body mass index (BMI) is a simple index of weight-for-height that is commonly used in classifying overweight and obesity in adult populations and individuals. It is defined as the weight in kilograms divided by the square of the height in meters (kg/m²).

The presence of excess body fat is usually accompanied by a wide array of divergent health disorders including respiratory problems, certain types of cancer, and osteoarthritis, which finally contribute to the described reduction in life expectancy. Obesity also typically promotes the appearance of a cluster of other interrelated diseases, in particular cardiovascular diseases, e.g., hypertension, atherogenic dyslipidemia, insulin resistance and type 2 diabetes. Insulin resistance in muscle cells reduces glucose uptake and storage of glucose as glycogen, whereas insulin resistance in liver cells results in impaired glycogen synthesis and a failure to suppress glucose production resulting in elevated blood glucose levels. Blood glucose levels are tightly regulated as a part of metabolic homeostasis such that normal blood glucose levels in humans are about 80 to 1 10 mg/dl except shortly after eating when the blood glucose level rises temporarily up to about 140 mg/dl. Type 2 diabetes is the most prominent disease related to failure of blood sugar regulation. For that reason, it is of high importance for subjects to avoid high blood glucose levels.

The present inventors have surprisingly found that 2-hydroxyoleic acid and derivatives thereof, such as compounds of formula (I), and pharmaceutical compositions comprising these compounds can be used for normalizing the blood glucose level in a subject in need thereof.

Accordingly, a first aspect of the invention relates to use of a compound of the general formula (I):

COOH-CHR-(CH₂)_m-CH=CH-(CH₂)_n-CH₃ (I), wherein R is selected from any group with a molecular weight from 14 to 200 Da, but preferably R is selected from OH, amino, d-₆alkyl, C₂-₆alkenyl, C₂-₆alkynyl, d-₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration, or

a pharmaceutically acceptable salt, ester or glyceride thereof, for preparing a pharmaceutical composition for lowering blood glucose. Preferably, the double bond is in cis configuration.

This first aspect may alternatively be formulated as a compound of formula (I)

COOH-CHR-(CH₂)_m-CH=CH-(CH₂)_n-CH₃ (I), wherein R is selected from any group with a molecular weight from 14 to 200 Da, but preferably R is selected from OH, amino, C_1-6alkyl, C₂.₆alkenyl, C₂.₆alkynyl, Ci.₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration, or

a pharmaceutically acceptable salt, ester or glyceride thereof, for use in lowering blood glucose levels in a mammal. Preferably, the double bond is in cis configuration. In an embodiment of the invention the compound of formula (I) is for treatment of a disorder or condition selected from the group consisting of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance and hyperglycemia. In a preferred embodiment of the present invention the compound of formula (I) is for treatment of a disorder or condition selected from the group consisting of diabetes type 2, insulin resistance syndrome, impaired glucose tolerance and hyperglycemia.

According to the compound of general formula (I) R may be selected from any group with a molecular weight from 14 to 200 Da, but preferably R is selected from OH, amino, C_1-6alkyl, C₂.₆alkenyl, C₂.₆alkynyl, Ci.₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂. In a preferred embodiment of the compound of formula (I), R is OH, amino group, e.g. NH₂, or O e alkyl, e.g. CH₃.

The term "alkyl", as used herein, unless otherwise indicated, includes saturated monovalent hydrocarbon radicals having straight or branched moieties. Examples of alkyl moieties include, but are not limited to, methyl, ethyl, propyl, isopropyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, and neopentyl. Alkyl is preferably Ci_-6 alkyl, i.e. groups containing from 1 to 6 carbon atoms, and for some embodiments of the present invention, more preferably Ci_-3 alkyl. The term "alkenyl", as used herein, unless otherwise indicated, includes alkyl moieties having at least one carbon-carbon double bond wherein alkyl is as defined above. Examples of alkenyl include, but are not limited to, ethenyl, propenyl, 1 -butenyl, and 2- butenyl. Alkenyl is preferably C₂-₆ alkyl, i.e. groups containing from 2 to 6 carbon atoms, and for some embodiments of the present invention, more preferably C₂-₃ alkenyl.

The term "alkynyl", as used herein, unless otherwise indicated, includes alkyl moieties having at least one carbon-carbon triple bond wherein alkyl is as defined above. Examples of alkynyl groups include, but are not limited to, ethynyl, 2-propynyl, 1 - butynyl, and 2-butynyl.

The term "alkoxy", as used herein, means an -O-alkyl group wherein "alkyl" is as defined above. Alkoxy furthermore refers to polyethers such as -0-(CH₂)i-6-0-CH_3. Examples include, but are not limited to methoxy, ethoxy, propoxy, isopropoxy, n- butoxy, sec-butoxy, tert-butoxy, pentoxy, 2-pentyloxy, isopentoxy, neopentoxy, hexoxy, 2-hexoxy, 3-hexoxy, and 3-methylpentoxy.

Any of the alkyl, alkenyl, alkynyl and alkoxy groups may optionally be substituted with one or more of substituents selected from -F, -CI, -CF₃, -CCI₃, -CH₃, -OH, -CN, -N0₂, - NH₂ and methoxy.

The term "amino group" as used herein includes NH₂, primary amino groups, such as methylamino and ethylamino, secondary amino groups, such as dimethylamino and diethylamino, and tertiary amino groups, such as trimethylamino.

In one preferred embodiment R may be selected from OH, NH₂, methoxy, F, CI, CF₃ and CCI₃. In another embodiment R may be selected from OH, methoxy, ethoxy, propoxy and isopropoxy, preferably OH or methoxy. In yet another embodiment R may be selected from OH, methyl, ethyl, propyl, isopropyl, ethenyl, propenyl, ethynyl and propynyl, preferably OH and methyl. In another embodiment R may be selected from OH, NH₂, methyl, methoxy, and CF₃.

In a further embodiment of the invention the compound of the general formula (I) is 2- hydroxyoleic acid, or a pharmaceutically acceptable base salt thereof. Examples of typical base salts include lithium, sodium, potassium, and magnesium salts or as elsewhere defined herein.

In yet a further embodiment of the invention the compound of general formula (I) is an ester compound, where the compound of general formula (I) has been reacted with methanol, ethanol, n-propanol, isopropanol or glycerol. In a preferred embodiment the ester compound has been formed by a reaction between glycerol and at least one fatty acid of general formula (I). In a particular preferred embodiment the ester compound has been formed by reacting glycerol with at least one 2-hydroxyoleic acid. In an especially preferred embodiment the compound is formed by reacting one glycerol molecule with one, two or three 2-hydroxyoleic acid molecules so as to form a monoglyceride, a diglyceride, or a triglyceride molecule.

In a further embodiment of the present invention the compound of formula (I) or a pharmaceutically acceptable salt, ester or glyceride thereof, is for treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance and hyperglycemia in an obese mammal. Preferably, the compound of formula (I) or a pharmaceutically acceptable salt, ester or glyceride thereof, is for treatment of diabetes type 2, insulin resistance syndrome, impaired glucose tolerance and hyperglycemia in an obese mammal.

Mammals are divided into two subclasses: the Prototheria, which includes the oviparous monotremes, and the Theria, which includes the placentals and live-bearing marsupials. Most mammals, including the six largest orders, belong to the placental group. The three largest orders, in descending order, are Rodentia (mice, rats, porcupines, beavers, capybaras, and other gnawing mammals), Chiroptera (bats), and Soricomorpha (shrews, moles and solenodons). The next three largest orders include the Carnivora (dogs, cats, weasels, bears, seals, and their relatives), the Cetartiodactyla (including the even-toed hoofed mammals and the whales) and the Primates to which the human species belongs. The relative size of these latter three orders differs according to the classification scheme and definitions used by various authors. In a preferred embodiment the mammal, is a cat, a dog or a human subject in particular a human subject. In the context of the present invention, the term "daily dosage" is meant to describe the daily dosage required for an average human subject having a weight of about 70 to 100 kg. In general, for administration to human patients the daily dosage level of the compounds in accordance with the present invention is in a range of from about 100 mg to about 15000 mg, more preferred from about 100 mg to about 8000 mg.

In one embodiment of the invention the compound is given in a daily dosage in a range of from about 100 mg to about 15000 mg, such as e.g., from about 500 mg to about 15000 mg, about 1000 mg to about 15000 mg, about 2000 mg to about 15000 mg, about 100 mg to about 10000 mg, about 100 mg to about 7500 mg, about 500 mg to about 5000 mg, about 1000 mg to about 5000 mg, about 2000 mg to about 5000 mg.

In another embodiment of the invention the compound is given in a daily dosage in a range of from about 100 mg to about 8000 mg, such as e.g., from about 100 mg to about 800 mg, about 500 mg to about 2000 mg, about 1000 mg to about 3000 mg, about 2000 mg to about 8000 mg.

In another embodiment the daily dosage lies in the range from about 100 to 500 mg, or from about 500 mg to about 1000 mg, or from about 1000 mg to about 1500 mg, or from about 1500 mg to about 2000 mg, or from about 2000 mg to about 2500 mg, or from about 2500 mg to about 3000 mg, or from about 3000 mg to about 3500 mg, or from about 3500 mg to about 4000 mg, or from about 4000 mg to about 4500 mg, or from about 4500 mg to about 5000 mg, or from about 5000 mg to about 5500 mg, or from about 5500 mg to about 6000 mg, or from about 6500 mg to about 7000 mg, or from about 7000 mg to about 7500 mg, or from about 7500 mg to about 8000 mg.

In another embodiment the daily dosage lies in the range from about 500 to about 2000 mg, such as e.g. about 600 mg to about 1800 mg, about 700 mg to about 1600 mg, about 800 mg to about 1400 mg, from about 900 mg to about 1200 mg, or about 1000 mg. In another embodiment the daily dosage lies in the range from about 200 mg to about 400 mg, or from about 400 mg to about 600 mg, or from about 600 mg to about 800 mg, or from about 800 mg to about 1000 mg, or from about 1000 mg to about 1200 mg, or from about 1200 mg to about 1400 mg, or from about 1400 mg to about 1600 mg, or from about 1600 mg to about 1800 mg, or from about 1800 mg to about 2000.

In another embodiment the daily dosage lies in the range from about 100 mg to about 200 mg, or from about 200 mg to about 300 mg, or from about 300 mg to about 400 mg, or from about 400 mg to about 500 mg, or from about 500 mg to about 600 mg, or from about 600 mg to about 700 mg, or from about 700 mg to about 800 mg, or from about 800 mg to about 900 mg, or from about 900 mg to about 1000 mg, or from about 1000 mg to about 1 100 mg, or from about 1 100 mg to about 1200 mg, or from about 1200 mg to about 1300 mg, or from about 1300 mg to about 1400 mg, or from about 1400 mg to about 1500 mg, or from about 1500 mg to about 1600 mg, or from about 1600 mg to about 1700 mg, or from about 1700 mg to about 1800 mg, or from about 1800 mg to about 1900 mg, or from about 1900 mg to about 2000 mg.

The skilled person will readily be able to determine the dosage levels required for a subject whose weight falls outside the average range, such as children and the elderly. The daily dosage may optionally be administered as a single dose or be divided in two or more doses, such as e.g. two, three, or four, for administration at different times during the day. The skilled person will appreciate that, in the treatment of insulin resistance or diseases associated with insulin resistance, compounds used in accordance with the presents invention may be taken as a single dose on an "as required" basis, i.e., as needed. The physician will in any event determine the actual dosage, which will be most suitable for any particular patient and it will vary with the age, weight and response of the particular patient. The above dosages are, of course only exemplary of the average case and there may be instances where higher or lower doses are merited and such are within the scope of the invention.

In a further embodiment of the present invention, the compounds for lowering blood glucose levels are administered in combination with one or more additional active compounds that act as anti-diabetic agents, anti-obesity agents and/or antihypertensive agents. Suitable anti-obesity agents include adrenergic agonists (e.g. phenylpropanolamine, ephedrine, pseudoephedrine, phentermine), 3 adrenergic receptor agonists, apolipoprotein-B secretion/microsomal triglyceride transfer protein (apo-B/MTP) inhibitors, MCR-4 agonists, cholecystokinin-A (CCK-A) agonists, monoamine reuptake inhibitors (e. g., sibutramine), sympathomimetic agents, serotoninergic agents, cannabinoid receptor antagonists (e.g. rimonabant (SR-141 , 716A)), dopamine agonists (e.g. bromocriptine), melanocyte-stimulating hormone receptor analogs, 5HT2c agonists, melanin concentrating hormone antagonists, leptin, leptin analogs, leptin receptor agonists, galanin antagonists, lipase inhibitors (i.e. orlistat), bombesin agonists, anorectic agents, Neuropeptide-Y antagonists, thyroxine, thyromimetic agents, dehydroepiandrosterones or analogs thereof, glucocorticoid receptor agonists or antagonists, orexin receptor antagonists, urocortin binding protein antagonists, glucagon-like peptide-1 receptor agonists, ciliary neurotrophic factors (e. g., Axokine), human agouti-related proteins (AGRP), ghrelin receptor antagonists, histamine 3 receptor antagonists or inverse agonists, neuromedin U receptor agonists, and the like.

Suitable anti-diabetic agents include metformin, glyburide, glimepiride, glipyride, glipizide, chlorpropamide, gliclazide, acarbose, miglitol, pioglitazone, rosiglitazone, balaglitazone, insulin, Gl- 262570, isaglitazone, JTT-501 , NN-2344, L895645, YM-440, R-1 19702, AJ9677, repaglinide, nateglinide, KAD1 129, AR- H039242, GW-409544, KRP297, AZ-242, AC2993, LY315902, P32/98, NVP-DPP-728A, and/or DPP IV inhibitors, such as sitagliptin, vildagliptin, saxagliptin and linapliptin.

Suitable anti-hypertensive agents include nifedipine, verapamil, diltiazem, hydralazine, isoxuprine, and minoxidil, losartan, candesartan, irbesartan, telmisartan, valsartan, eprosartan, captopril, fosinopril, enalapril, lisinopril, quinapril, benazepril, fentiapril, ramipril, moexipril, prazosin, methyldopa, hydralazine, amiloride, spironolactone, Triamterene, Atenolol, Bisoprolol, Metoprolol, Nadolol, Propranolol, Timolol, and clonidine.

Other anti-diabetic agent, anti-obesity agent and/or anti-hypotensinsive agents, including the preferred agents set forth below, are well known, or will be readily apparent in light of the instant disclosure, to one of ordinary skill in the art. Preferably, use of compounds of formula (I) of the present invention for lowering the blood glucose level of a subject in need thereof, and combination therapies, may be administered in conjunction with exercise and a sensible diet. In a further embodiment of the present invention, the compounds of formula (I), or pharmaceutically acceptable salts, esters or glycerides thereof, for lowering blood glucose levels are administered in combination with one or more additional active compounds selected from rimonabant, surinabant, SLV-319, orlistat, cetilistat, sibutramine, lorcaserin, oxyntomodulin, taranabant, tesofensine sergliflozin, metformin, exenatide, pramlintide, liraglutide, obinepitide, phentermine, phendimetrazine, insulin, leptin, sitagliptin, vildagliptin, saxagliptin, linapliptin and pharmaceutically acceptable salts thereof.

In another embodiment of the present invention the compound or one or more compounds of formula (I) is/are the only active compound(s) administered for lowering the blood glucose level of a subject. The compound of formula (I) in itself, i.e. for example and preferably 2-hydroxyoleic acid, or a base salt thereof, is capable of providing the lowering of the blood glucose level. The compounds to be used in accordance with the invention can be administered orally, buccally or sublingually in the form of tablets, capsules (including soft gel capsules), ovules, elixirs, solutions or suspensions, which may optionally contain flavouring or colouring agents. The compounds of the invention are preferably administered orally, such as a pharmaceutical composition formulated for oral administration.

Tablets may contain excipients such as microcrystalline cellulose, lactose, sodium citrate, calcium carbonate, dibasic calcium phosphate, glycine, and starch (preferably corn, potato or tapioca starch), disintegrants such as sodium starch glycollate, croscarmellose sodium and certain complex silicates, and granulation binders such as polyvinylpyrrolidone, hydroxypropylmethylcellulose (HPMC), hydroxypropylcellulose (HPC), sucrose, gelatine and acacia. Additionally, lubricating agents such as magnesium stearate, stearic acid, glyceryl behenate and talc may be included. Solid compositions of a similar type may also be employed as fillers in gelatin capsules. Preferred excipients in this regard include lactose, starch, cellulose, milk sugar or high molecular weight polyethylene glycols.

Gels may contain excipients as well known within the technical area. Especially, gel formulations such as those used for administering fish oils are suitable for use in the present invention.

In general a tablet and/or capsule formulation could typically contain between about 10 mg to about 1000 mg of a compound for use in accordance with the present invention whilst tablet fill weights may for example range from 50 mg to 3000 mg.

In a preferred embodiment of the present invention the pharmaceutical composition is for oral administration, such as a tablet, capsule, caplet, gel or a liquid. A further aspect of the invention relates to a method of lowering blood glucose levels in a mammal in need thereof, comprising administering a therapeutically effective amount of a compound of formula (I)

COOH-CHR-(CH₂)_m-CH=CH-(CH₂)_n-CH₃ (I), wherein R can be any group with a molecular weight from 14 to 200 Da, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration or a mixture thereof, or

a pharmaceutically acceptable salt, ester or glyceride thereof. Preferably, the double bond is in cis configuration.

In an embodiment the method is for treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance and hyperglycemia. In a preferred embodiment the method is for treatment of diabetes type 2, insulin resistance syndrome, impaired glucose tolerance and hyperglycemia.

In another embodiment the mammal is a cat, a dog or a human subject and in particular an obese mammal such as an obese human or an obese cat or dog. In a further embodiment the compound of formula (I) to be administered is 2- hydroxyoleic acid, or a pharmaceutically acceptable base salt, ester or glyceride thereof. In a preferred embodiment the 2-hydroxyoleic acid is formulated into a pharmaceutical composition such as a tablet, capsule, caplet, gel or a liquid, which is formulated for oral administration.

It should be noted that, according to the present invention, embodiments and features described in the context of one of the aspects of the present invention also apply to the other aspects and embodiments of the invention.

Examples

Example 1

Effect of 2-hydroxyoleic acid on the glucose homeostasis as measured by an oral glucose tolerance test.

Thirty-two (32) male C57BL/6J mice were used in the present study. At 4 weeks of age the animals were shipped to the animal facility. The mice were housed under a 12:12 UD cycle (lights on at 04:00 AM and lights off at 04:00 PM) and in temperature and humidity controlled rooms.

Upon arrival, 8 of the animals were offered a low fat diet (10% energy from fat; 12450B, Research Diets, New Jersey) diet and 24 of the animals placed on an energy-dense high-fat diet (60% energy from fat; D12492, Research Diets, New Jersey) and water ad libitum. After approximately 14 weeks of housing, treatment with the 2-hydroxyoleic acid was initiated. Animals were stratified according to their body weight on experimental day -1 and grouped in 4 groups for per orally treatment with vehicle, 2- hydroxyoleic acid or sibutramine as indicated below.

Group 1 , Vehicle, milli-Q water

Concentration, dose: N/A

Diet, normal diet (LF Control)

Group 2, Vehicle, milli-Q water

Concentration, dose: N/A

Diet, energy-dense high-fat diet (HF Control) Group 3, 2-hydroxyoleic acid (400mg/kg)

Concentration, dose: 80 mg/ml; 400mg/kg

Diet, energy-dense high-fat diet (2-OHOA).

Group 4, sibutramine (10mg/kg)

Concentration, dose: 2 mg/ml; 10mg/kg

Diet, energy-dense high-fat diet (Sibutramine). Prior to start of experiment the animals were mock-dosed for 7 days to accustom them to the oral gavage paradigm. The animals were treated (PO, dosing volume: 5 ml/kg) with 2-hydroxyoleic acid (400mg/kg), Sibutramine (10mg/kg) or vehicle for 30 days. Body weight was measured every second day during the treatment period. Before termination of the experiment, all animals were subjected to an oral glucose tolerance test.

Oral glucose tolerance test

Animals were over night fasted. Blood samples for blood glucose ("Stick method") measurements were taken from a tail vein at time points 0, 15, 30, 60, and 120 after oral administration of 2g/kg glucose. Blood glucose levels were determined as measures for glucose clearance as evaluated by calculating the area under the curve (AUC).

Statistical evaluation of the data was carried out using one-way analysis of variance (ANOVA) with Newman-Keuls Multiple Comparison Test between all groups. Outliers were defined by Grubb's rule for outliers and excluded from the final data-set.

Conclusions

At the time of the oral glucose tolerance test the animals that had been fed energy- dense high-fat diet exhibited a statistically significant increase of blood glucose level of approximately 29% as compared to the animals that had received the normal low fat diet (p<0.05). When comparing the blood glucose levels of the animals treated with 2- hydroxyoleic acid to the vehicle group that also had received a energy-dense high-fat diet, these blood glucose levels displayed significant lower glucose level at all time points after glucose administration, thus giving rise to a significant lower AUC value Figure 1 A and B. In fact the AUC value of the 2-hydroxyoleic acid treated animals exhibited exactly the same blood glucose level as observed in animals placed on a normal low fat diet and was statistically undistinguishable from that group (p>0.05). In contrast treatment with sibutramine had no effect on lowering the blood glucose levels and still differed statistically significant from the animals on the normal low fat diet (p<0.05) (Figure 1 A and B). Accordingly, it appears that 2-hydroxyoleic acid and sibutramine act by different molecular mechanisms and that only 2-hydroxyoleic acid shows the ability to lower blood glucose levels in the treated animals. Thus, the ability of 2-hydroxyoleic acid to improve blood glucose levels is not a general effect observed for all compounds with the ability to lower the body weight of a subject.

Example 2

Dose response effect of 2-hydroxyoleic acid on the glucose homeostasis as measured by an oral glucose tolerance test.

Forty (40) male C57BL/6J mice were used in the present study. At 4 weeks of age the animals were shipped to the animal facility and single housed. The mice were housed under a 12:12 L/D cycle (lights on at 04:00 AM and lights off at 04:00 PM) and in temperature and humidity controlled rooms.

Upon arrival, the animals were offered an energy-dense high-fat diet (60% energy from fat; D12492, Research Diets, New Jersey) and water ad libitum. After approximately 14 weeks of housing, treatment with the 2-hydroxyoleic acid compound was initiated. Animals were stratified according to their body weight on experimental day -1 and grouped in 5 groups for further oral treatment with vehicle, 2-hydroxyoleic acid or sibutramine as indicated below.

Group 1 , Vehicle, milli-Q water

Concentration, dose: N/A

Group 2, 2-hydroxyoleic acid (100mg/kg)

Concentration, dose: 20 mg/ml; 100mg/kg Group 3, 2-hydroxyoleic acid (200mg/kg) Concentration, dose: 40 mg/ml; 200mg/kg

Group 4, 2-hydroxyoleic acid (400mg/kg)

Concentration, dose: 80 mg/ml; 400mg/kg

Group 5, sibutramine (10mg/kg)

Concentration, dose: 2 mg/ml; 10mg/kg

Prior to start of experiment the animals were mock-dosed for 7 days to accustom them to the oral gavage paradigm. The animals were treated (PO, dosing volume: 5 ml/kg) with 2-hydroxyoleic acid (100, 200 or 400 mg/kg), sibutramine (10mg/kg) or vehicle for 42 days. Before termination of the experiment, all animals were subjected to an oral glucose tolerance test. Body weight and 24 hours food intake were measured daily during the first week of treatment and thereafter twice a week throughout the rests of the treatment period. The body weight was expressed as the temporal course of body weight and body weight gain in percent of the body weight day 0.

Table 1 : Body weight gain in % of day 0

Statistics: p-value vs. vehicle; One Way ANOVA with Dunnet's post hoc test.

Conclusion

As illustrated in table 1 chronic treatment with 2-hydroxyoleic acid significantly and dose dependency lowered the body weight as compared to the vehicle control. In animals treated with 400 mg/kg 2-hydroxyoleic acid the body weight was reduced by 24% whereas sibutramine, the reference compound, caused a reduction in body weight of 13 %.

Oral glucose tolerance test

Animals were over night fasted (food removed at 04.00 PM the day before). Thirty (30) minutes before glucose administration (time -30min) a blood sample was drawn just prior to oral dosing with the respective compounds (dosed at time -30min). Blood samples for blood glucose ("Stick method") measurements were taken from a tail vein at time points -30, 0, 15, 30, 60, 120 and 240 minutes after oral administration of 1 g/kg glucose (Glucose 500 mg/ml, Fresenius Kabi, Sweden). Blood glucose levels were determined as measures for glucose clearance as evaluated by calculating the area under the curve (AUC).

Statistical evaluation of the data was carried out using one-way analysis of variance (ANOVA) with Dunnet's post-hoc analysis between control and treatment groups in cases where statistical significance was established (^*p<0.05; ^**p<0.01 or ^***p<0.001 ). Outliers were defined by Grubb's rule for outliers and excluded from the final data-set.

Table 2: OGTT Glucose day 42

Statistics: p-value vs. vehicle; One Way ANOVA with Dunnet's post hoc test.

Conclusion

As seen in table 2, animals treated with 100mg/kg 2-hydroxyoleic acid displayed no significant different fasting glucose level than the vehicle group. However, animals treated with 200mg/kg 2-hydroxyoleic acid displayed slightly lower fasting glucose levels than the vehicle group whereas animals treated with 2-hydroxyoleic acid at 400mg/kg displayed a significant lower fasting glucose level (t=-30 min) at two and four hours after glucose administration, thus giving rise to a significant lower AUC value. In contrast, as observed in example 1 , treatment with sibutramine that caused a reduction in body weight of 13% showed no significant effect on the blood glucose level at any of the time points or when comparing the AUC values to the vehicle group (Table 1 and 2). Accordingly, it appears that 2-hydroxyoleic acid and sibutramine act by different molecular mechanisms and that only 2-hydroxyoleic acid shows the ability to lower blood glucose levels in the treated animals. Thus, the ability of 2-hydroxyoleic acid to improve blood glucose levels is not a general effect observed for all compounds with the ability to lower body weight. Example 3

Effect of 2-hydroxyoleic acid on body weight and blood glucose level

Fifty (50) male C57BL/6J mice were used in this study. At 6 weeks of age the animals were shipped to the animal facility. The mice were housed under a 12:12 L/D cycle (lights on at 04:00 AM and lights off at 04:00 PM) and in temperature and humidity controlled rooms.

Fourty (40) mice were fed on a high fat diet without significant carbohydrate (80% of weight from fat, approximately 1 % of weight from carbohydrates) for 6 weeks to induce glucose intolerance without significant body weight increase. Ten animals received a normal low fat diet and were used as controls. After 6 weeks feeding the animals on the high fat diet were stratified according to their glucose intolerance on experimental day -4 and grouped in 4 groups. From experimental day -4 on body weight was registered every day at the same hour. One group of mice on the high fat, low carbohydrate diet was treated daily with 400mg/kg of 2-hydroxyoleic acid as the sodium salt whilst continuing on diet for 14 days. As a positive control a similar group of mice to those given 2-hydroxyoleate were given the anti-diabetic drug rosiglitazone (3mg/kg p.o.) daily. The fourth group of animals received 400mg/kg of 2-hydroxystearic acid daily, which is the saturated chemical congener of 2-hydroxyoleic acid.

Oral glucose tolerance test

Animals were fasted for 5h before the test. Blood samples for blood glucose ("Stick method") measurements were taken from a tail vein directly before the oral glucose tolerance test to determine fasting blood glucose level and 120 min after oral administration of 2g/kg glucose.

Statistical evaluation of body weight and oral glucose tolerance test data was carried out using one-way analysis of variance (ANOVA) with Dunnett's post-hoc analysis between the high fat control group and all other groups in cases where statistical significance was established (^*p<0.05; ^**p<0.01 or ^***p<0.001 ). Statistical evaluation of the fasting blood glucose was carried out using Student's two-tailed t-test for unpaired data (^*p<0.05). Outliers were defined by Grubb's rule for outliers in all data sets and excluded from the final data-set.

Conclusions

The mice on the high fat, low carbohydrate diet showed no excess body fat relative to chow control prior to dosing and, thus have to be considered a non-obese animal model (Fig 2A). None of the compounds did provoke a significant effect on animal body weight after a 14 day treatment (Fig 2B). Fig 2C shows that 2-hydroxyoleate but not rosiglitazone, which is a PPAR gamma activator, reduced the fasting blood glucose concentration in the mice. Moreover, another 2-hydroxy fatty acid, 2-hydroxystearic acid, did also not reduce the fasting blood glucose level in those mice treated with this compound. This is a relevant finding as 2-hydroxystearic acid has a chemically identical structure to 2-hydroxyoleic acid with exception of the missing double bond, which demonstrates the importance of the unsaturation for the blood glucose lowering effect of 2-hydroxy oleic acid. The blood glucose levels measured 120 min after initiation of the oral glucose tolerance test demonstrated that the high fat, low carbohydrate diet alone caused an impairment in glucose disposal relative to low fat chow fed mice (Fig 2D). This impairment was totally corrected by treatment with 2- hydroxyoleate, whereas rosiglitazone gave partial correction of the hyperglycaemia.

Thus, 2-hydroxyoleic acid, sodium salt restores normoglycaemia in a non-obese mouse model of impaired glucose tolerance demonstrating that the anti-diabetic effect of 2- hydroxyoleate is independent of any anti-obesity action.

Example 4

Effect of 2-hydroxy oleate on body weight changes and fasting blood glucose level Male C57BI/6 mice were fed on a high fat diet (SDS Western diet) designed to induce obesity and insulin resistance for a period of 23 weeks. The mice were then allocated to treatment with 2-hydroxyoleic acid sodium salt or an ad-lib fed control group or a group that were pair-fed, that is given the same amount of food, to the group of mice that were given 2-hydroxyoleate. The purpose of this latter control group was to achieve a similar degree of weight loss to that achieved by the 2-hydroxyoleate-treated mice. A further group of mice were given the anti-obesity drug sibutramine. During the first two days a dose of 400 mg/Kg of 2-hydroxyoleate and 10 mg/Kg sibutramine were administered to the respective groups. In the period of day 2 to 6 (a transition period) the dose was varied from 400 to 200 mg/Kg 2-hydroxyoleate and 10 to 5 mg/Kg sibutramine, respectively.

Fig 3A shows the weight reduction during treatment and demonstrates similar weight reduction in the 2-hydroxyoleate-treated mice to that in the sibutramine-treated mice. Weight loss in the 2-hydroxyoleate treated mice was greater than in pair-fed treated mice illustrating that the weight reduction in the 2-hydroxyoleate-treated mice is not solely through reduction in food intake. Fig 3B shows that 2-hydroxyoleate alone reduced fasting blood glucose after 7 days treatment. Similar results were seen after 15 days treatment (Fig 3C).

Thus, although Sibutramine and 2-hydroxy oleate induced a similar level of fat loss, only 2-hydroxyoleate significantly reduced the fasting blood glucose.

Claims

1. Use of a compound of the general formula (I): COOH-CHR-(CH₂)_m-CH=CH-(CH₂)_n-CH₃ (I), wherein R represents a group with a molecular weight from 14 to 200 Da selected from OH, amino, Ci_₆alkyl, C₂-₆alkenyl, C₂-₆alkynyl, Ci_₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration, or

a pharmaceutically acceptable salt, ester or glyceride thereof, for preparing a pharmaceutical composition for lowering blood glucose.

2. Use according to claim 1 , wherein the pharmaceutical composition is for treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia.

3. Use according to claim 1 , wherein the pharmaceutical composition is for treatment of diabetes type 2, insulin resistance syndrome, impaired glucose tolerance or hyperglycemia.

4. Use according to any one of claims 1 to 3, wherein R is selected from OH, amino group, e.g. NH₂, or d-₆ alkyl, e.g. CH₃.

5. Use according to any one of claims 1 -4, wherein the compound of the general formula (I) is 2-hydroxyoleic acid, or a pharmaceutically acceptable base salt, ester or glyceride thereof.

6. Use according to any one of claims 1 -5, wherein the pharmaceutical composition is for treatment of diabetes type 2, insulin resistance syndrome, syndrome

X, impaired glucose tolerance and hyperglycemia in an obese mammal.

7. Use according to claim 6, wherein the mammal, is a human subject or the mammal is a cat or a dog.

8. Use according to any one of the preceding claims, wherein the compound of formula (I) is administered as a daily dosage in a range of from about 100 mg to about 15 g, more preferred from about 100 mg to about 8 g, even more preferred from about 200 mg to about 2000 mg.

9. Use according to any one of the preceding claims, wherein the pharmaceutical composition is administered sequentially or simultaneously with one or more additional active substance(s), such as rimonabant, surinabant, SLV-319, orlistat, cetilistat, sibutramine, lorcaserin, oxyntomodulin, taranabant, tesofensine sergliflozin, metformin, exenatide, pramlintide, liraglutide, obinepitide, phentermine, phendimetrazine, insulin, leptin, sitagliptin, vildagliptin, saxagliptin, linapliptin and pharmaceutically acceptable salts thereof.

10. Use according to any one of the preceding claims, wherein the pharmaceutical composition is for oral administration, such as a tablet, capsule, caplet, gel or as a liquid.

1 1 . A compound of formula (I) COOH-CHR-(CH₂)_m-CH=CH-(CH₂)_n-CH₃ (I), wherein R represents a group with a molecular weight from 14 to 200 Da selected from OH, amino, d-₆alkyl, C₂-₆alkenyl, C₂-₆alkynyl, Ci-₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration, or

a pharmaceutically acceptable salt, ester or glyceride thereof, for use in lowering blood glucose levels in a mammal.

12. The compound according to claim 1 1 , wherein R is selected from OH, amino group, e.g. NH₂, or Ci_₆ alkyl, e.g. CH₃.

13. The compound according to any one of claims 1 1 or 12, wherein the compound of the general formula (I) is 2-hydroxyoleic acid, or a pharmaceutically acceptable base salt, ester or glyceride thereof.

14. The compound according to any one of claims 1 1 -13 for use in the treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia.

15. The compound according to any one of claims 1 1 -13 for use in the treatment of diabetes type 2, insulin resistance syndrome, impaired glucose tolerance or hyperglycemia.

16. The compound according to any one of claims 1 1 -13 for use in the treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia in an obese mammal or in an obese cat or dog.

17. The compound according to any one of claims 1 1 -13 for use in the treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia in an obese human subject or in an obese cat or dog.

18. The compound according to any one of claims 1 1 -17, wherein the compound of formula (I) is administered as a daily dosage in a range of from about 100 mg to about 15 g, more preferred from about 100 mg to about 8 g, even more preferred from about 200 mg to about 2000 mg.

19. A pharmaceutical composition comprising the compound according to any one of the claims 1 1 -18.

20. The pharmaceutical composition according to claim 19, wherein the pharmaceutical composition is administered sequentially or simultaneously with one or more additional active substance(s), such as rimonabant, surinabant, SLV-319, orlistat, cetilistat, sibutramine, lorcaserin, oxyntomodulin, taranabant, tesofensine sergliflozin, metformin, exenatide, pramlintide, liraglutide, obinepitide, phentermine, phendimetrazine, insulin, leptin, sitagliptin, vildagliptin, saxagliptin, linapliptin and pharmaceutically acceptable salts thereof.

21. The pharmaceutical composition according to any one of claims 19 or 20, wherein the pharmaceutical composition is for oral administration, such as a tablet, capsule, caplet, gel or as a liquid.

22. A method of lowering blood glucose levels in a mammal in need thereof, comprising administering a therapeutically effective amount of a compound of formula (I)

COOH-CHR-(CH₂)_m-CH=CH-(CH₂)_n-CH₃ (I), wherein R represents a group with a molecular weight from 14 to 200 Da selected from OH, amino, Ci_₆alkyl, C₂-₆alkenyl, C₂-₆alkynyl, Ci_₆alkoxy, F, CI, CF₃, CCI₃, CN or N0₂, m and n are independently selected from an integer of 3 to 10, and the double bond is in cis or trans configuration, or

a pharmaceutically acceptable, ester or glyceride salt thereof.

23. The method according to claim 22, wherein R is selected from OH, amino group, e.g. NH₂, or d-₆ alkyl, e.g. CH₃.

24. The method according to any one of claims 22 or 23, wherein the compound of the general formula (I) is 2-hydroxyoleic acid, or a pharmaceutically acceptable base salt, ester or glyceride thereof.

25. The method according to any one of claims 22-24 for treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia.

26. The method according to any one of claims 22-24 for treatment of diabetes type 2, insulin resistance syndrome, impaired glucose tolerance or hyperglycemia.

27. The method according to any one of claims 22-24 for treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia in an obese mammal, or in an obese cat or dog.

28. The method according to any one of claims 22-24 for treatment of diabetes type 2, insulin resistance syndrome, syndrome X, impaired glucose tolerance or hyperglycemia in an obese human subject or in an obese cat or dog.

29. The method according to any one of claims 22-24, wherein the compound of formula (I) is administered as a daily dosage in a range of from about 100 mg to about 15 g, more preferred from about 100 mg to about 8 g, even more preferred from about 200 mg to about 2000 mg.

30. The method according to any one of claims 22-24, wherein the compound of formula (I) is comprised in a pharmaceutical composition.

31 . The method according to claim 30, wherein the pharmaceutical composition is administered sequentially or simultaneously with one or more additional active substance(s), such as rimonabant, surinabant, SLV-319, orlistat, cetilistat, sibutramine, lorcaserin, oxyntomodulin, taranabant, tesofensine sergliflozin, metformin, exenatide, pramlintide, liraglutide, obinepitide, phentermine, phendimetrazine, insulin, leptin, sitagliptin, vildagliptin, saxagliptin, linapliptin and pharmaceutically acceptable salts thereof.

32. The method according to any one of claims 30-31 , wherein the pharmaceutical composition is for oral administration, such as a tablet, capsule, caplet, gel or as a liquid.